Question: What was the language used during the time of the Achaemenid Empire?
Paraphrase: During the Achaemenid Empire, what was the language used?
SPARQL (Wikidata):  select distinct ?obj where { wd:Q389688 wdt:P37 ?obj . ?obj wdt:P31 wd:Q45762 } 
Answer: Elamite, Median, Sumerian